Process of forming sodium compounds



Patented May 4, 1926.

UNITED STATES 1,583,661 PATENT "or-Pics.

HERBERT EDWIN GOCKSEDGE, F HARTFORD, ENGLAND, ASSTGNOB TO THE SOLVAYPROCESS COMPANY, 01' SOLVAY, NEW YORK, A CORPORATION OF NEW YORK.

PROCESS OF FORMING SODIUM COMPOUNDS.

' No Drawing.

To all whom it may concern:

Be it known that I, HERBERT EDWIN Coonsnncn, a subject of the King ofGreat Britain, residing at Hartford. Chester. in 5 the county of Chesterand Kingdomof England, have invented certain new and useful Improvementsin Processes of Forming Sodium Compounds, of which the following is aspecification. i

1922, Serial No. 598,020, I have described a new sodium compound whichis represented by the formula Na CO,.iiNaI-ICO and which ischaracterized by its fine needlelike form and refractive indices of orabout 1.435 and 7 about 1.526.

I have therein described a process for its formation by suitably heatingsodium bicarbonate, which should not be absolutely dry but should havesome water content. It has also been proposed to make the compound frombicarbonate-carbonate mixtures.

I have now discovered and my new process is based on the discovery thatit is not necessary'to use the bicarbonate of soda in the formation ofthe new compound, but that-it ma be made directly from the carbonate anwithout any bicarbonate admixture by heating the carbonate in thepresence of a carbon dioxide gas, and at a temperature and for a timesuch that its conversion into sodium bicarbonate'is not effected. Watereither as liquid or gas should also be present A temperature of about 75 to 100 C. is suitable, for example,

for operations at ordina pressure.

For example, dry s ium carbonate is heated in a closed vessel at 90 C.to 100 C. while a slow current of a carbon dioxidewater vapor gasmixture (e. g. made b passing carbon dioxide through hot waterg 1spassed through the vessel and n contact with the carbonate.

The gas is in part absorbed and the material in the vessel graduallyincreases in volume, indicati that the reaction is proceeding.Microscopic examination of the product shows abundance of the thin,elongated, needle-like particles characteristic of the newcarbonate-bicarbonate compound.

The gas evolved in the production oi the In an application for LettersPatent ofthe United States filed by me October 30,

Application filed November 9, 1923. Serial No. 673,827.

source of the CO and water, or water vapor, for the process which is thesubject of this application.

When in the claims I speak of the compound Na GO .3NaHCO,

I means the substance as described in my earlier application which ischaracterized by its line needle-like crystal form and the refractiveindices'of a about'1.435 and y about 1.526 and when in the claims I usethe phrase carbonate of sodium materia containing less CO than thecomparison is between equal quantities by weight of the material and ofthe and obviously the expression carbonate of sodium material? includesnot only a dry sodium carbonat but also mixtures of the carbonate withother materials including, of course, such a material when alreadycontaining some of the new compounds and/ or even some bicarbonate. e

What I claim as new and desire to secure by Letters Patent is 1. Theprocess which comprises treating carbonate of sodium material containingless CO than which comprises the incor oration of a limited amount of COin sai material until substantial amounts of V 2. The process of formingthe substance which. comprises exposing a given amount less CO than ofcarbonate of sodium material containing Na CO BNaHCO,

to an'atmosphere containing carbon dioxid and H and maintaining saidmaterial in said atmosphere at a temperature below that which vcausecarbonate of sodium to refrain from reaction with CO or which wouldconvert the material into carbonate, until the compound as distinguishedfrom bicarbonate alone or a carbonate-bicarbonate mixture is pro duced.

3. The process of forming the substance Na CO fiNaHCO which comprisesheating sodium carbonate "at a temperatureof about 100 C. in thepresence of carbon dioxide and Water (and under conditions'of treatmentfavorable to the formation or said. compound).

i. The process of forming the substance us co emnoo,

which comprises driving off from crude bi- 1,5ease1 carbonate materialby moderate heat, less than that which would convert the material intocarbonate, limited amounts of CO and H 0 until the compound is formed insubstantial amounts and leading the gases from said reaction intocontact with carbonate of sodium material containing less CO than na coenano'o, and exposing a given amount, of the carb0n ate material to saidatmosphere and maintaining it therein until the compound Na CO .3NaHCO,

is formed in substantial amounts and thereafter maintaining theconditions thus establlshed, whereby the sodium carbonate-bicarbonatecompound I as distinguished from bicarbonate alone or acarbonate-blcarbonate mixture is produced as the result ofthe conversionof both the bicarbonate as well as the carbonate material into thecompound having the formula set forth.

In testimony whereof I afix my signature, this 23rd day of October,1923.

HERBERT EDN oosanen.

